1. Field of the Invention
The present invention relates to a method and apparatus for tracking moving objects (i.e., movable things such as cars, bicycles, and animals) in pictures by processing time-series pictures.
2. Description of the Related Art
Early detection of a traffic accident can not only enhance a success rate in life saving by speedy rescue operation, but also alleviate accident-related traffic congestion by speedup of the police inspection at the site. Therefore, various kinds of automation in recognition of traffic accident are expected. In order to achieve a high recognition rate of traffic accidents, it is necessary to correctly track moving objects by processing pictures captured by a camera.
In tracking moving objects, it is particularly difficult to differentiate overlapped moving objects in a picture from each other and to track moving objects without being affected by variations in luminance of the moving objects due to such ones as the shade of clouds or buildings.
The former difficulty can be overcome by a method of calculating a spatio-temporal correlation based on a spatio-temporal Markov model, which has been disclosed in the publication of JP 2001-148019-A whose inventors are the same as those of the present application. The latter difficulty can be overcome by using a differential picture (G. L. Gimel'farb, “Texture Modeling by Multiple Pairwise Pixel Interactions”, IEEE trans. PAMI, Vol. 18, No. 11, 1996, pp 1110–1114).
However, there are still technical challenges in achieving a high success rate of tracking moving objects with a suitable method of converting the differential picture for incorporation into the correlation-based method.